The present invention relates generally to packaging and more specifically to thermoformed reclosable blister packs.
Clear plastic display packages are commonly used in retail sales environments where it is desired to present merchandise for visual inspection by the customer. Blister packages feature a transparent bubble, typically produced through a thermoforming process, which is sealed to a backing card. One conventional method of attaching the card is to place a heat-activated adhesive on it and heat the card to adhere the flanges of the thermoformed bubble thereto. Display packages with blisters adhered to paperboard backing cards are effective in showcasing the merchandise. Undesirably, however, adhesive backed cards are expensive and require an additional process step, viz., heating, to seal the package. Furthermore, once opened, these packages cannot be easily reclosed because the backing card is typically ripped apart and destroyed during opening.
Thermoformed plastic packages having integrally hinged covers with positive snap locking mechanisms are also known in the art and are commonly referred to as xe2x80x9cclam-shells.xe2x80x9d These packages provide an attractive and functional container, but can require high initial tooling costs and high material costs not always justified by the product to be carried in the package. The tooling for these clam-shell designs also has size limitations in modern production equipment. Further, the clam-shell package requires a separate insert card to communicate the contents of the package.
Another popular and inexpensive blister-card design includes the blister having a flange around its periphery that folds unto itself, commonly referred by those skilled in the art as a xe2x80x9cflange-fold.xe2x80x9d The flange-fold, which is essentially a 180 degree fold, forms a groove or channel into which the backing card is slidably inserted. The backing card is then typically stapled to the blister to hold it in place, thereby eliminating the need for adhesives. This design has at least two drawbacks. First, the staple lends a cheap or chintzy appearance to the package which, undesirably, may also be imported to the contents. Further, forming the flange-fold requires an additional, time-consuming process step after thermoforming and requires an additional costly piece of equipment to perform the flange fold.
What is needed is an economical reclosable display package which uses cost-effective materials and an economy thereof, and whose manufacture can be performed cost-effectively.
The present invention is a reclosable blister container in which a backing card is slidably and removably retained in the blister without requiring staples or adhesives. The blister includes elongated grooves on opposite sides thereof that slidingly receive the backing card. The blister includes a step that is preferably curved, which facilitates slidable entry of the backing card into the blister.
In one form thereof, the present invention provides a reclosable container comprising a thermoplastic blister having a bubble defining a container cavity. A flange extends laterally from the bubble. A side wall extends upwardly from the flange. The side wall defines an elongated groove extending along at least one third of its length. A skirt extends laterally from the sidewall, the skirt defining a plane spaced from the flange. A backing card is slidably and removably received in the groove and abuts the flange.
In a preferred form, the flange comprises a step connecting it to the skirt, and the step is angled relative to the flange. With this arrangement, the step facilitates slidable receipt of the backing card into the blister. More preferably, the step is curved.
In a further preferred form, either the skirt or the flange, or both, include a protrusion that mates with the backing card and retains the backing card in the blister. In a further preferred form, the protrusion fits into a complementary opening in the backing card. In another preferred form, the protrusion extends from the skirt and projects over the step such that an edge of the backing card fits under the protrusion and is held against the step.
The reclosable container is preferably and conveniently integrally formed as one piece.
In another form thereof, the present invention provides a reclosable container comprising a thermoplastic blister having a bubble defining a container cavity. A flange extends laterally from the bubble and a side wall extends upwardly from the flange. The side wall defines a groove at a lower end thereof, and a backing card is slidably and removably retained in the groove and abuts the flange. The flange is curved upwardly at an end thereof, which facilitates slidable receipt of the backing card into the blister.
In a preferred form thereof, the groove extends continuously along at least one third of the length of the side wall. More preferably, the blister is integrally formed in one piece.
One advantage of the present invention is that it eliminates the costly adhesive-backed cards employed in prior art containers and it also avoids the concomitant process steps of heating the card and adhering it to the blister. Instead, with containers embodying the present invention, the card is simply fed into the blister and is retained by the blister alone. With the present invention, no staples, glue, adhesives, tape or any other tools are necessary to secure the backing card to the blister.
Another advantage of the present invention is that containers embodying it can be opened and closed as many times as desired without destroying the container. To open the container, the backing card is simply pried away from the blister and slid therefrom. The container can be easily re-closed by reinserting the card and sliding it back into the blister.
Yet another advantage of the present invention is that it avoids the time-consuming and costly process step of xe2x80x9cflange-foldingxe2x80x9d the blister. The present invention also obviates the costly piece of equipment whose sole purpose is to flange-fold the blisters. Further, the present invention eliminates the unsightly staple and process step to install it which is typically associated with flange-folded blisters. Indeed, the present invention fulfills a long-felt need for an inexpensive replacement to the flange-folded blister design.
Still another advantage of the present invention is that it provides a reasonable alternative for clam-shell containers. As mentioned above, clam-shell type containers provide an attractive and functional reclosable container, but their high cost is not always justified by the cost of the product being packaged therein. Flange-folded containers, on the other hand, are often not perceived in the industry as a suitable replacement for clam-shells because the poor quality perceived by the consumer of the flange-folded container can be transferred to the product, thereby negatively affecting sales. Of course, with any product, the packaging effects the perceived quality of the product. Because containers in accordance with the present invention provide a high quality appearance, they offer a plausible alternative to costly clam-shells for many packaging applications.
Amazingly, containers made in accordance with the present invention not only provide a more attractive package than one which is flange-folded, but they also provide a significant cost savings over a flange-folded product. Specifically, it is estimated that a container made in accordance with the present invention would cost approximately 25% less than its flange-folded counterpart.